植物科学最前線 6: 41 ( 2015)ࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊ㄏᑟᶵᵓ▼ᕝ 㞞ᶞᇶ♏⏕≀Ꮫ◊✲ᡤ ⏕≀㐍໬◊✲㒊㛛⥲ྜ኱Ꮫ㝔኱Ꮫ ⏕࿨⛉Ꮫ◊✲⛉ ᇶ♏⏕≀Ꮫᑓᨷ
ࠛ444-8585 ឡ▱┴ᒸᓮᕷ᫂኱ᑎ⏫Ꮠす㒓୰ 38
Molecular mechanisms of stem cell formation in the moss Physcomitrella patens
Key words: cell cycle; Physcomitrella patens; reprogramming; stem cell; wounding
Masaki Ishikawa
Division of Evolutionary Biology, National Institute for Basic Biology
Department of Basic Biology, School of Life Sciences, Graduate School for Advanced Studies
38 Nishigonaka, Myodaiji, Okazaki, 444-8585, Japan㸯. ࡣࡌࡵ࡟ከ⣽⬊⏕≀࡟ࡳࡽࢀࡿᖿ⣽⬊ࡣࠊ⮬ᕫ」〇⬟ຊ࡜ศ໬ࡋࡓ⣽⬊ࢆ⏕ࡳฟࡍ⬟ຊࡢ୧᪉ࢆࡶࡗࡓ⣽⬊࡛࠶ࡾࠊከ⣽⬊యไࡢ㉳Ⅼ࡜࡞ࡿ⣽⬊࡛࠶ࡿࠋᖿ⣽⬊ࡣࠊ⏕≀ಶయࡢ≉ᐃࡢሙᡤ࡟⥔ᣢࡉࢀ࡚࠾ࡾࠊ✀Ꮚ᳜≀࡛ࡣ࣓ࣜࢫࢸ࣒࡛⥔ᣢࡉࢀ࡚࠸ࡿ (Weigel and Jurgens, 2002)ࠋࡲࡓศ໬ࡋࡓ⣽⬊࠿ࡽᖿ⣽⬊ࢆㄏᑟࡍࡿࡇ࡜ࡶྍ⬟࡛࠶ࡿࠋ౛࠼ࡤࠊ✀Ꮚ᳜≀ࡢ⤌⧊∦ࢆ࣮࢜࢟ࢩࣥࠊࢧ࢖ࢺ࢝࢖ࢽࣥࢆྵࡴᇵᆅ࡛ᇵ㣴ࡍࡿ࡜ࠊศ໬⣽⬊࠿ࡽ࢝ࣝࢫࡀㄏᑟࡉࢀࠊ᳜≀࣍ࣝࣔࣥ⃰ᗘ࡟౫Ꮡࡋ࡚ᖿ⣽⬊ࢆྵࢇࡔ࣓ࣜࢫࢸ࣒ࡀᙧᡂࡉࢀࡿࠋࡲࡓ့ங㢮࡛ࡶࠊᩘ✀㢮ࡢ㑇ఏᏊࢆⓎ⌧ࡉࡏࡿࡇ࡜࡟ࡼࡗ࡚ࠊ⧄⥔ⱆ⣽⬊ࢆጞࡵ࡜ࡋࡓከࡃࡢศ໬⣽⬊ࢆࠊ⬇ᛶᖿ⣽⬊ᵝࡢ⣽⬊㸦iPS⣽⬊㸧࡟ኚ໬ࡉࡏࡿࡇ࡜ࡀྍ⬟࡟࡞ࡗ࡚࠸ࡿ (Masip et al., 2010)ࠋ
㏻ᖖࠊศ໬⣽⬊ࡣ⣽⬊ቑṪࢆ೵Ṇࡋ࡚≉ᐃࡢ⣽⬊ᶵ⬟ࢆᯝࡓࡋ࡚࠸ࡿࠋࡑࡢࡓࡵࠊศ໬⣽⬊ࡀᖿ⣽⬊࡬ኚ໬ࡍࡿ㐣⛬㸦ᖿ⣽⬊໬㸧࡛ࡣࠊศ໬⣽⬊ࡀ⣽⬊࿘ᮇࢆ෌㛤ࡍࡿ࡜࡜ࡶ࡟ࠊࡑࡢศ໬⣽⬊ࡀᣢࡗ࡚࠸ࡿ⣽⬊ࡢᛶ㉁ࢆࣜࢭࢵࢺࡋᖿ⣽⬊ࡢᛶ㉁ࢆ⋓ᚓࡍࡿࠋࡲࡓࠊศ໬⣽⬊ࡢ⣽⬊࿘ᮇࡢ෌㛤ࠊ࠾ࡼࡧࡑࡢ㐍⾜ࡣࠊᖿ⣽⬊ࡢᛶ㉁ࢆ⋓ᚓࡍࡿࡓࡵ࡟ᚲせ࡞ࣉࣟࢭࢫ࡛࠶ࡿࡇ࡜ࡀศ࠿ࡗ࡚
ࡁࡓ (Che et al., 2007; Hanna et al., 2009; Kim et al., 2011)ࠋࡑࡢࡓࡵࠊᖿ⣽⬊໬ࡢ㐣⛬࡛ࡣࠕ⣽⬊࿘ᮇࡢ෌㛤࣭㐍⾜ࠖ࡜ࠕ⣽⬊ᛶ㉁ࡢኚ໬ࠖࡀ༠ㄪⓗ࡟ไᚚࡉࢀࡿᚲせࡀ࠶ࡿࡀࠊࡑࡢศᏊᶵᵓࡣࡼ
ࡃศ࠿ࡗ࡚࠸࡞࠸ࠋ➹⪅ࡀᡤᒓࡋ࡚࠸ࡿ◊✲ࢢ࣮ࣝࣉ࡛ࡣࠊศ໬⣽⬊࠿ࡽᖿ⣽⬊ࢆᐜ᫆࡟ㄏᑟ࡛ࡁࡿࢥࢣ᳜≀ࢭࣥ㢮࡟ᒓࡍࡿࣄ࣓ࢶࣜ࢞ࢿࢦࢣ㸦Physcomitrella patens㸧ࢆ⏝࠸࡚ࠊࡑࡢㅦ࡟ྲྀࡾ⤌ࢇ࡛ࡁࡓࠋࡑࡇ࡛ᮏ✏࡛ࡣࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊໬࡟࠾ࡅࡿ⣽⬊࿘ᮇࡢ෌㛤࡜⣽⬊ᛶ㉁ࡢኚ໬ࢆ༠ㄪⓗ࡟ไᚚࡋ࡚࠸ࡿศᏊᶵᵓ࡟ࡘ࠸࡚ゎㄝࡍࡿࠋ㸰. ᖿ⣽⬊໬◊✲ࡢࣔࢹ᳜ࣝ≀࡜ࡋ࡚ࡢࣄ࣓ࢶࣜ࢞ࢿࢦࢣࢥࢣ᳜≀ࡣࠊ㝣ୖ᳜≀ࡢ࡞࠿࡛᭱ࡶྂࡃศᒱࡋ࡚࠾ࡾࠊࢭࣥ㢮ࠊࢱ࢖㢮ࠊࢶࣀࢦࢣ㢮ࡢ㸱ࡘ࡟M. Ishikawa- 1BSJ- Revi ew 6: 41 ( 2015)

植物科学最前線 6: 42 ( 2015)ศ࠿ࢀࡿࠋࢭࣥ㢮࡟ᒓࡍࡿࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡣࠊ࣮ࣚࣟࢵࣃࠊ໭⡿࡟ᗈࡃศᕸࡋ࡚࠾ࡾࠊ㓄അయୡ௦ࡀඃඛⓗ࡞⏕άྐࢆࡶࡘࠋࡲࡓࠊ㝣ୖ᳜≀࡛᭱ࡶᐜ᫆࡟㑇ఏᏊࢱ࣮ࢤࢸ࢕ࣥࢢࢆ⾜࠺ࡇ࡜ࡀ࡛ࡁࠊ⿕Ꮚ᳜≀௨እࡢ㝣ୖ᳜≀࡜ࡋ࡚ࡣึࡵ࡚඲ࢤࣀ࣒ゎᯒࡀ᏶஢ࡋ࡚࠸
ࡿ (Rensing et al., 2008; Zimmer et al.,2013)ࠋࡑࡢࡓࡵ㑇ఏᏊ᝟ሗࢆ฼⏝ࡋ࡚ࠊ ᅗ㸯.㸦A㸧ࢡࣟࣟࢿ࣐࡜㸦B㸧ⱼⴥయࠋ㑇ఏᏊ◚ቯࠊ࠶ࡿ࠸ࡣ⥳Ⰽ⺯ගࢱࣥࣃ㸦ࢫࢣ࣮ࣝࣂ࣮ࡣࠊ[A] 100 µm, [B] 1 mm㸧

ࢡ㉁㸦GFP㸧࡞࡝ࡢ࣏࣮ࣞࢱ࣮㑇ఏᏊࢆ┠ⓗࡢ⟠ᡤ࡟ᐜ᫆࡟ᤄධࡍࡿࡇ࡜ࡀ࡛ࡁࠊ㑇ఏᏊࡢᶵ⬟ゎᯒࢆ⾜࠸ࡸࡍ࠸ࠋࡉࡽ࡟ࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡣࠊᖿ⣽⬊ࢆㄏᑟࡋࡸࡍࡃࠊ⣽⬊࡛ࣞ࣋ࣝࡢほᐹࡀᐜ࡛᫆࠶ࡿࠋࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡣࠊ⬊ᏊࡀⓎⱆࡍࡿ࡜ࢡࣟࣟࢿ࣐㡬➃ᖿ⣽⬊ࡀᙧᡂࡉࢀࠊඛ➃ᡂ㛗࡜⣽⬊ศ⿣ࢆ⧞ࡾ㏉ࡍࡇ࡜࡛ࠊ⣽⬊ෆ࡟୸࠸ⴥ⥳యࢆᐦ࡟ᣢࡕࠊ㞄᥋ࡍࡿ⣽⬊ྠኈࢆ㝸࡚ࡿ⣽⬊ቨࢆ⣽⬊ࡢ㛗㍈࡟ᑐࡋ࡚ᆶ┤࡟ᙧᡂࡍࡿࢡࣟࣟࢿ࣐⣽⬊ࢆ⏕ࡳฟࡍ㸦ᅗ 1A㸹 Kofuji and Hasebe, 2014)ࠋࡇࢀ࡟ࡼ
ࡾࠊ⣽⬊ࡀ୍ิ࡟୪ࢇࡔࢡࣟࣟࢿ࣐ࡀᙧᡂࡉࢀࡿࠋࡋࡤࡽࡃࡍࡿ࡜ࠊࢡࣟࣟࢿ࣐㡬➃ᖿ⣽⬊ࡣࠊ࢝࢘ࣟࢿ࣐㡬➃ᖿ⣽⬊࡬࡜ኚ໬ࡋࠊ⣳㗽ᆺࡢⴥ⥳యࢆ⣽⬊ࡢ୰࡟ࡲࡤࡽ࡟ᣢࡕࠊ㝸ቨࢆ⣽⬊ࡢ㛗㍈࡟ᑐࡋ࡚ᩳࡵ࡟ᙧᡂࡍࡿ࢝࢘ࣟࢿ࣐⣽⬊ࢆసࡾฟࡋ࡚࠸ࡃࠋࡲࡓࠊ୍㒊ࡢ࢝࢘ࣟࢿ࣐⣽⬊࠿ࡽⱆศ໬ࡀ⏕ࡌࠊⱼ࡜ⴥ࠿ࡽ࡞ࡿⱼⴥయࡀᙧᡂࡉࢀࡿ㸦ᅗ 1B㸧ࠋࡑࡢⴥࡣࠊ୰⫘㒊ศࢆ㝖࠸୍࡚ᒙࡢ⣽⬊ࡢࡳ࡛ᵓᡂࡉࢀ࡚࠸ࡿࠋࡑࡋ࡚ࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢⴥࢆⱼⴥయ࠿ࡽษࡾ㞳ࡍ࡜ࠊ᳜≀࣍ࣝࣔࣥ࡞ࡋ࡛ษ᩿㠃࡟㠃ࡋࡓⴥ⣽⬊࡛⣽⬊࿘ᮇࡢ෌㛤ࡀ࠾ࡇࡾࠊษ᩿ᚋ 2 ᪥௨ෆ࡟ࢡࣟࣟࢿ࣐㡬➃ᖿ⣽⬊ࡀᙧᡂࡉࢀࡿ㸦ᅗ 2㸹Ishikawa et al., 2011)ࠋࡇࡢࡼ࠺࡟ࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡣࠊᐜ᫆࡟ᖿ⣽⬊ࢆㄏᑟࡍࡿࡇ࡜ࡀྍ⬟࡛࠶ࡿ࡜࡜ࡶ࡟ࠊᖿ⣽⬊໬ࡍࡿ⣽⬊ࢆ≉ᐃࡋࠊࡑࡢ⣽⬊ࡢືⓗኚ໬ࢆほᐹࡍࡿࡇ࡜ࡀ࡛ࡁࡿࡓࡵࠊᖿ⣽⬊໬◊✲ࡢඃࢀࡓࣔࢹࣝ⏕≀ࡢ୍ࡘ࡛࠶ࡿ࡜ゝ࠼ࡿࠋ➹⪅ࡀᡤᒓࡋ࡚࠸ࡿ◊✲ࢢ࣮ࣝࣉ࡛ࡣࠊࡇࢀࡽࡢࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢ฼Ⅼࢆ⏕࠿ࡋࠊᖿ⣽⬊໬࡟㛵ࢃࡿᅉᏊࡢゎᯒࢆ⾜࠸ࠊ⣽⬊࿘ᮇ࡜⣽⬊ᛶ㉁ࡢኚ໬ࢆ༠ㄪⓗ࡟ไᚚࡍࡿศᏊᶵᵓࡢ୍➃ࢆ᫂ࡽ࠿࡟ࡋ࡚ࡁࡓࠋᅗ㸰. ษ᩿ⴥࡢ⤒᫬ⓗኚ໬ᖿ⣽⬊໬ࡋࡓ⣽⬊ࢆ㙨࡛⾲ࡋ࡚࠸ࡿࠋ
㸦ࢫࢣ࣮ࣝࣂ࣮ࡣࠊ300 µm㸧෗┿ᥦ౪㸸Liechi Zhang
M. Ishikawa- 2BSJ- Revi ew 6: 42 ( 2015)

植物科学最前線 6: 43 ( 2015)

㸱. ࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊໬࡟࠾ࡅࡿ⣽⬊࿘ᮇࡢ෌㛤ከ⣽⬊యไࢆᵓ⠏ࡋ࡚࠸ࡿศ໬⣽⬊ࡢከࡃࡣࠊ⣽⬊࿘ᮇ G1 ᮇ࡛೵Ṇࡋ࡚࠸ࡿࠋቑṪᅉᏊࡸയᐖ࡞࡝࡟ࡼࡗ่࡚⃭ࡀຍࢃࡿ࡜ࠊ୍㒊ࡢ⣽⬊ࡀ⣽⬊࿘ᮇࢆ෌㛤ࡉࡏ⣽⬊ቑṪࡀ㉳ࡇࡿࠋ┿᰾⏕≀ࡢ⣽⬊࿘ᮇࡢ෌㛤࣭㐍⾜ࡣࠊࢧ࢖ࢡࣜࣥ࡜ࢧ࢖ࢡࣜࣥ౫Ꮡᛶ࢟ࢼ࣮ࢮ (Cyclin-dependent kinase:CDK) ࡢ」ྜయ࡟ࡼࡗ࡚ไᚚࡉࢀ࡚࠸ࡿ (Komaki and Sugimoto, 2012)ࠋࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢࢤࣀ
࣒࡟ࡶࠊࡇࢀࡽࢆࢥ࣮ࢻࡍࡿ㑇ఏᏊࡀಖᏑࡉࢀ࡚࠸ࡿ (Rensing et al., 2008)ࠋࡑࡇ࡛ࠊᖿ⣽⬊໬࡟࠾ࡅࡿࡇࢀࡽࡢ㑇ఏᏊⓎ⌧ࡸ CDK ࢟ࢼ࣮ࢮάᛶࢆㄪ࡭ࡓ࡜ࡇࢁࠊ⣽⬊࿘ᮇࡢ G1 ᮇ࠿ࡽ S ᮇ࡬ࡢ⛣⾜᫬࡟ᶵ⬟ࡍࡿ D ࢱ࢖ࣉíࢧ࢖ࢡࣜࣥ (CYCD) ࡀࠊษ᩿ᚋ 12 ᫬㛫┠࠶ࡓࡾ࡛ษ᩿㠃࡟㠃ࡍࡿ⣽⬊࡛Ⓨ⌧ࡀୖ᪼ࡋࠊࡑࡢᚋࠊG2 ᮇ࠿ࡽ M ᮇ࡬ࡢ⛣⾜ࢆไᚚࡍࡿ B ࢱ࢖ࣉíࢧ࢖ࢡࣜࣥࡀⓎ⌧ࡋ࡚ࡁࡓ (Ishikawa et al., 2011)ࠋ୍᪉ࠊ⣽⬊࿘ᮇไᚚࡢ୰ᚰⓗ࡞ᙺ๭ࢆᯝࡓࡍ A ࢱ࢖ࣉ CDK(CDKA) ࡣࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣ࡟ࡣ CDKA;1 ࡜ CDKA;2 ࡢ஧ࡘࡀᏑᅾࡋ࡚࠸ࡿࡀࠊ࡝ࡕࡽࡶษ᩿๓ࡢⴥ⣽⬊඲య࡛Ⓨ⌧ࡋ࡚࠸ࡓࡀࠊࡑࡢ࢟ࢼ࣮ࢮάᛶࡣ CYCD ࡢⓎ⌧࡜࡜ࡶ࡟ୖ᪼ࡋࡓࠋࡲࡓ⣽⬊㉁ศ⿣๓࡟ࢳ࣑ࢪࣥ࢔ࢼࣟࢢ࡛࠶ࡿ EdU ࡢྲྀࡾ㎸ࡳࡀほᐹࡉࢀࡓࠋࡇࢀࡽࡢࡇ࡜࠿ࡽࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢⴥ⣽⬊ࡣࠊ௚ࡢከ⣽⬊⏕≀ࡢศ໬⣽⬊࡜ྠᵝ࡟ G1 ᮇ࡟೵Ṇࡋ࡚࠾ࡾࠊษ่᩿⃭࡟ࡼࡗ࡚⣽⬊࿘ᮇࡀ G1 ᮇ࠿ࡽ෌㛤ࡍࡿ࡜ண᝿ࡉࢀࡓࠋ
࡜ࡇࢁࡀࠊࣇ࣮ࣟࢧ࢖ࢺ࣓ࢺ࣮࡛ࣜⴥ⣽⬊ࡢ DNA 㔞ࢆㄪ࡭࡚ࡳࡿ࡜ࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢⱼⴥయࡣ༙ᩘయୡ௦࡛࠶ࡿ࡟ࡶ࠿࠿ࢃࡽࡎࠊ
࡯ࡰ 2C ࡢ᰾ DNA 㔞࡛࠶ࡿࡇ࡜ࡀศ࠿ࡗࡓ (Ishikawa etal., 2011)ࠋࡇࡢࡇ࡜ࡣࠊⴥ⣽⬊ࡣ⣽⬊࿘ᮇࡢ G1 ᮇ࡛ࡣ࡞ࡃࠊS ᮇᚋ༙࡛೵Ṇࡋ࡚࠸ࡿࡇ࡜ࢆព࿡ࡋ࡚࠾ࡾࠊ➹⪅ࡣ௨ୗ࡟ᣲࡆࡿ⣽⬊࿘ᮇ෌㛤ࡢྍ⬟ᛶࢆ⪃࠼࡚࠸ࡿࠋ㸱í㸯. 㹑ᮇᚋ༙࠿ࡽࡢ⣽⬊࿘ᮇ෌㛤ⴥ⣽⬊ࡣ S ᮇᚋ༙࡛೵Ṇࡋ࡚ࠊDNA 」〇ࡀᮍ᏶஢࡛࠶ࡿࡇ࡜ࡀ⪃࠼ࡽࢀࠊษ᩿ᚋ࡟」〇ࡉࢀ࡚࠸࡞࠸㡿ᇦ࡛ࡢ DNA 」〇ࡀ㉳ࡇࡿ࡜࠸࠺ྍ⬟ᛶ࡛࠶ࡿ㸦ᅗ 3A㸧ࠋS ᮇࡣ DNA 」〇ࡀ㉳ࡇࡿ᫬ᮇ࡛࠶ࡿࡀࠊ⣽⬊ࡢᛶ㉁ࢆኚ໬ࡉࡏࡿ᫬ᮇ࡛ࡶ࠶ࡿࡇ࡜ࡀศ࠿ࡗ࡚ࡁࡓࡓࡵࠊS ᮇ࠿ࡽࡢ⣽⬊࿘ᮇ෌㛤ࡣࠊᖿ⣽⬊໬ࡢᛶ㉁ࢆㄏᑟࡍࡿࡢ࡟㐺ษ࡞᫬ᮇ࡛࠶ࡿࡇ࡜ࡀ᥎ᐹ࡛ࡁࡿࠋື᳜≀ࢆၥࢃࡎࠊ࡝ࡢయ⣽⬊࡛ࡶ㑇ఏ᝟ሗࡣྠࡌ࡛࠶ࡿࡓࡵࠊྛࠎࡢయ⣽⬊ࡣࠊⓎ⏕ࡸᡂ㛗ࡢ㐣⛬࡟ᛂࡌ࡚Ⓨ⌧ࡉࡏࡿ㑇ఏᏊࢆษࡾ᭰࠼ࠊ⤌⧊࣭ჾᐁ≉␗ⓗ࡞ᶵ⬟ࢆ⋓ᚓࡍࡿࠋࡇࡢࡼ࠺࡞㑇ఏᏊⓎ⌧ไᚚࡢኚ໬ࡣࠊ㌿෗ᅉᏊ࡟ࡼࡿไᚚ࡟ຍ࠼࡚ࠊDNA ࡢ࣓ࢳࣝ໬ಟ㣭ࡸࣄࢫࢺࣥࢱࣥࣃ
ࢡ㉁ࡢ໬Ꮫಟ㣭࡜࠸ࡗࡓ࢚ࣆࢪ࢙ࢿࢸ࢕ࢵࢡಟ㣭࡟ࡼࡗ࡚ࡶไᚚࡉࢀ࡚࠸ࡿࠋࡑࡢࡓࡵࠊศ໬⣽⬊࠿ࡽᖿ⣽⬊࡬ኚ໬ࡍࡿࡓࡵ࡟ࡣࠊ࢚ࣆࢪ࢙ࢿࢸ࢕ࢵࢡಟ㣭ࡢᾘཤ࠾ࡼࡧ෌ᵓᡂࡀᚲせ࡛࠶ࡿࠋ౛࠼ࡤࠊࢩࣙ࢘ࢪࣙࣂ࢚ࡢᡂ⹸ཎᇶ࡟࠾ࡅࡿ⣽⬊ศ໬㌿᥮ࢆక࠺ჾᐁ෌⏕㐣⛬࡛ࡣࠊS ᮇࡀ㏻ᖖࡢ⣽⬊࿘ᮇ࡟࠾ࡅࡿ S ᮇ࡟ẚ࡭࡚㛗ࡃ࡞ࡗ࡚࠾ࡾࠊࡇࡢ S ᮇࡢ㛗ࡉࡀ௨๓ࡢ⣽⬊ᛶ㉁ࢆࣜࢭࢵ
ࢺࡍࡿࡢ࡟ᚲせ࡛࠶ࡿ (Sustar and Schubiger, 2005)ࠋࡲࡓࢩࣙ࢘ࢪࣙࣂ࢚ࡢ⬇Ⓨ⏕࡛ࡣࠊS ᮇࡢDNA 」〇ࡢ㛫࡟ࠊ㌿෗άᛶ࡟ാࡃࣄࢫࢺࣥ H3 ࡢ 4 ␒┠ࡢࣜࢪࣥࡀࢺ࣓ࣜࢳࣝ໬ࡉࢀࡓ H3K4me3
ࡸࠊ㌿෗ᢚไ࡟ാࡃࣄࢫࢺࣥ H3 ࡢ 27 ␒┠ࡢࣜࢪࣥࡀࢺ࣓ࣜࢳࣝ໬ࡉࢀࡓ H3K27me3 ࡀࠊࡑࡢࡼ
࠺࡞ಟ㣭ࢆཷࡅ࡚࠸࡞࠸ࣄࢫࢺࣥ H3 ࡟⨨ࡁ᥮ࢃࡾࠊDNA 」〇ᚋࠊ෌ࡧࣄࢫࢺࣥಟ㣭ࡀ࠾ࡇࡿࡇ
࡜ࡀ♧ࡉࢀࡓ (Petruk et al., 2012)ࠋࡇࢀࡽࡢࡇ࡜࠿ࡽࠊS ᮇ࡛௨๓ࡢ࢚ࣆࢪ࢙ࢿࢸ࢕ࢵࢡಟ㣭ࢆࣜࢭࢵࢺࡋࠊ࠶ࡽࡓ࡞㑇ఏᏊⓎ⌧ࣃࢱ࣮ࣥࢆ⋓ᚓࡍࡿࡓࡵࡢศᏊᶵᵓࡀാ࠸࡚࠸ࡿࡼ࠺࡛࠶ࡿࠋ
M. Ishikawa- 3BSJ- Revi ew 6: 43 ( 2015)

植物科学最前線 6: 44 ( 2015)ᅗ㸱. ࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊໬࡛࠾ࡇࡿ⣽⬊࿘ᮇ෌㛤ࡢࣔࢹࣝ(A) S ᮇᚋ༙࠿ࡽࡢ⣽⬊࿘ᮇ෌㛤ࠋ(B) DNA ቑᖜࢆకࡗࡓ⣽⬊࿘ᮇ෌㛤ࠋ(C) DNA ಟ᚟ࢆకࡗࡓ⣽⬊࿘ᮇ෌㛤ࠋヲ⣽ࡣᮏᩥཧ↷ࠋࣄ࣓ࢶࣜ࢞ࢿࢦࢣ࡛ྠᵝ࡞ࡇ࡜ࡀ㉳ࡇࡗ࡚࠸ࡿ࡝࠺࠿ࡣᐃ࠿࡛࡞࠸ࡀࠊⴥ⣽⬊ࡀ S ᮇ࡛೵Ṇࡋ࡚࠸ࡿࡢ࡛࠶ࢀࡤࠊษ᩿ᚋ࡟」〇ࡉࢀ࡚࠸࡞࠸㡿ᇦ࡛ࡢ DNA 」〇ࡀ㉳ࡇࡿ࡜࡜ࡶ࡟ࠊ࢚ࣆࢪ࢙ࢿࢸ࢕ࢵࢡಟ㣭ኚ໬ࡶㄏᑟࡍࡿࡇ࡜࡛ࠊⴥ⣽⬊࠿ࡽࢡࣟࣟࢿ࣐㡬➃ᖿ⣽⬊࡬࡜⣽⬊ࡢᛶ㉁ࢆኚ໬ࡉࡏ࡚࠸ࡿࡢ࠿ࡶࡋࢀ࡞࠸ࠋ㸱í㸰. 㹂㹌㸿ቑᖜࢆక࠺⣽⬊࿘ᮇ෌㛤ษ᩿๓ࡢⴥ⣽⬊ࡣ S ᮇᚋ༙࡛೵Ṇࡋ࡚࠸ࡿࡀࠊษ᩿࡟ࡼࡾ DNA 」〇ࡔࡅ࡛࡞ࡃࠊDNA 」〇࡜ࡣ␗࡞ࡿ DNA ྜᡂࡀ≉ᐃࡢࢤࣀ࣒㡿ᇦ࡛࠾ࡇࡿྍ⬟ᛶࡶ⪃࠼ࡽࢀࡿ㸦ᅗ 3B㸧ࠋᐇ㝿࡟ࠊDNA」〇࡜ࡣ␗࡞ࡿ DNA ྜᡂࡀ࠸ࡃࡘ࠿ࡢ⏕≀࡛ぢࡘ࠿ࡗ࡚࠸ࡿࠋ⿕Ꮚ᳜≀࡛ࡣࠊ⬺ศ໬ࡋ࢝ࣝࢫᙧᡂࡍࡿ࡜ࡁ࡟཯᚟㓄ิࡢ DNA ቑᖜࡀ㉳ࡇࡿࡼ࠺࡛࠶ࡿ (Kunakh, 1999)ࠋࡲࡓ㓝ẕ࡛ࡢ rDNAࡢ㑇ఏᏊቑᖜ (Ide et al., 2010) ࡸࠊ࢞ࣥ⣽⬊࡛ࡢ⣽⬊ቑṪ㛵㐃㑇ఏᏊࡢቑᖜ (Schwab, 1998) ࡀ▱ࡽࢀ࡚࠸ࡿࠋࡇࢀࡽࡢࡇ࡜ࡣࠊ⣽⬊ቑṪ࡟㛵ࢃࡿ㑇ఏᏊࢆቑᖜࡉࡏࡿࡇ࡜࡛⣽⬊ቑṪ⬟ࢆ㧗ࡵ࡚࠸ࡿࡼ࠺࡛࠶ࡿࠋࣄ࣓ࢶࣜ࢞ࢿࢦࢣ࡛ྠࡌࡼ࠺࡞ࡇ࡜ࡀ㉳ࡇࡗ࡚࠸ࡿࡢ࡛࠶ࢀࡤࠊษ᩿ᚋ࡟࠾ࡇࡿ DNA ྜᡂࡣࠊ⣽⬊ศ⿣ࢆ೵Ṇࡉࡏ࡚࠸ࡿⴥ⣽⬊ࡢศ⿣άᛶࢆ㧗ࡵࡿാࡁࡀ࠶ࡿࡢ࠿ࡶࡋࢀ࡞࠸ࠋ㸱í㸱. 㹂㹌㸿ಟ᚟ࢆక࠺⣽⬊࿘ᮇ෌㛤DNA 」〇௨እࡢ DNA ྜᡂࡀక࠺ูࡢྍ⬟ᛶ࡜ࡋ࡚ࠊDNA ಟ᚟ࡀ࠾ࡇࡗ࡚࠸ࡿྍ⬟ᛶࡀ⪃࠼ࡽࢀࡿࠋษ᩿࡜࠸࠺യᐖࢩࢢࢼࣝ࡟ࡼࡗ࡚ࠊษ᩿㠃࡟㠃ࡋࡓⴥ⣽⬊࡛ DNA ᦆയࡀ㉳ࡇࡗ࡚࠸ࡿ
ྍ⬟ᛶࡀ⪃࠼ࡽࢀࠊṇ☜࡟ፉ⣽⬊࡟㑇ఏ᝟ሗࢆఏ࠼ࡿࡓࡵ࡟ࠊᖿ⣽⬊໬ࡢ㐣⛬࡛ࠊDNA ᦆയࢆಟ᚟ࡉࡏ࡚࠸ࡿࡢ࠿ࡶࡋࢀ࡞࠸ࠋ
M. Ishikawa- 4BSJ- Revi ew 6: 44 ( 2015)

植物科学最前線 6: 45 ( 2015)ࡲࡓ⣽⬊ࡢศ໬㌿᥮ࡢ㐣⛬࡟࠾࠸࡚ࡶ DNA ಟ᚟⣔ࡀάᛶ໬ࡉࢀࡿࡇ࡜ࡀ▱ࡽࢀ࡚࠸ࡿࠋࣄࣕࢡࢽࢳࢯ࡛࢘ࡣࠊⴥ⫗⣽⬊࠿ࡽ⟶≧せ⣲࡬ࡢศ໬㌿᥮㐣⛬࡛ࠊDNA ಟ᚟࡟ఝࡓ DNA ྜᡂࡀ㉳ࡇࡿࡇ࡜ࡀሗ࿌ࡉࢀ࡚࠸ࡿ (Sugiyama et al., 1995)ࠋࡲࡓ࣐࢘ࢫࡢⓎ⏕ึᮇ࡟࠾࠸࡚ࠊ༸ࡸ⢭Ꮚࢆసࡾฟࡍጞཎ⏕Ṫ⣽⬊࡛ࡣࠊ㑇ఏᏊⓎ⌧ࣃࢱ࣮ࣥࢆయ⣽⬊ᆺ࠿ࡽ⏕Ṫ⣽⬊ᆺ࡬࡜ኚ᥮ࡋ࡞ࡅࢀࡤ࡞ࡽ࡞࠸ࡀࠊࡇࡢ㐣⛬࡟࠾࠸࡚ࠊጞཎ⏕Ṫ⣽⬊ࢆ G2 ᮇ࡛೵Ṇࡉࡏࠊࡑࡢ㛫࡟ DNA ಟ᚟⣔ࢆ౑ࡗ࡚DNA ࡢ࣓ࢳࣝ໬ࣃࢱ࣮ࣥࡢኚ໬ࢆ㉳ࡇࡍ (Hajkova et al., 2008; Hajkova et al., 2010)ࠋࣄ࣓ࢶࣜ࢞ࢿ
ࢦࢣࡢᖿ⣽⬊໬ࡢ㐣⛬࡟࠾࠸࡚ࡶࠊࡑࡢࡼ࠺࡞ DNA ಟ᚟⣔ࡀάᛶ໬ࡉࢀࠊᖿ⣽⬊໬㐣⛬࡟ᚲせ࡞࢚ࣆࢪ࢙ࢿࢸ࢕ࢵࢡ࡞ኚ໬ࢆᘬࡁ㉳ࡇࡋ࡚࠸ࡿࡢ࠿ࡶࡋࢀ࡞࠸ࠋ୍᪉ࠊ
ࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢษ᩿ⴥࢆ DNA 」〇ࡢ㜼ᐖ๣࡛࠶ࡿ࢔ࣇ࢕ࢹ࢕ࢥ࡛ࣜࣥฎ⌮ࡍࡿ࡜ࠊDNA ྜᡂ࡜⣽⬊㉁ศ⿣ࡀᢚไࡉࢀࡿࡀࠊࢡࣟࣟࢿ࣐㡬➃ᖿ⣽⬊ࡢ≉ᚩ࡛࠶ࡿඛ➃ᡂ㛗ࡀほᐹࡉࢀࡓ (ᅗ 4; Ishikawa et al., 2011)ࠋࡇࡢࡇ࡜࠿ࡽࠊษ᩿ᚋ࡟࠾ࡇࡿ DNA ྜᡂࡣࠊ⣽⬊ࡢᛶ㉁ࢆኚ໬ࡉ
ࡏࡿࡓࡵ࡟ᚲせ࡞㐣⛬࡜࠸࠺ࡼࡾࡣࠊ⣽⬊ศ⿣࡟ᚲせ࡞㐣⛬࡛ࡣ࡞࠸࠿࡜⪃࠼ࡽࢀࡿࠋ㸱í㸲. ≉␗࡞⣽⬊࿘ᮇ෌㛤࡜⣽⬊ᛶ㉁ࡢኚ໬⿕Ꮚ᳜≀ࡸື≀࡟࠾࠸࡚ࠊศ⿣ࢆ೵Ṇࡋࡓయ⣽⬊ࡣ⣽⬊࿘ᮇ G㸯ᮇ࡛೵Ṇࡋ࡚࠸ࡿࡀࠊቑṪᅉᏊ࡞࡝ࡢ่⃭ࢆឤ▱ࡍࡿ࡜ࠊࡑࡢ⣽⬊ࡣ෌ࡧ⣽⬊ศ⿣ࡢ࿘ᮇ࡟ධࡿࡇ࡜ࡀ࡛ࡁࡿࠋศ⿣ࢆ೵Ṇࡋ࡚࠸ࡿ⣽⬊࡟ࡣࠊ᪂ࡋ࠸⣽⬊࿘ᮇ࡟ධࡿ࠿ྰ࠿Ỵᐃࡍࡿ࣏࢖ࣥࢺࠊRestriction point (R Ⅼ) ࡀ G1ᮇ࡟Ꮡᅾࡋ࡚࠸ࡿࠋࡑࡋ୍࡚ᗘ R Ⅼࢆ㐣ࡂࡿ࡜ࠊ⣽⬊࿘ᮇࡣ㏵୰࡛Ṇࡲࡿࡇ࡜࡞ࡃ୍ᕠࡍࡿࠋ࡜
ࡇࢁࡀࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢⴥ⣽⬊ࡣ S ᮇᚋ༙࡛೵Ṇࡋ࡚࠸ࡿࡢ࡛ࠊG1 ᮇ࡟࠶ࡿ R Ⅼࢆ㉸࠼࡚࠸ࡿ࡜⪃࠼ࡽࢀࡿࠋࡑࡢࡓࡵࠊఱࡽ࠿ࡢไᚚᶵᵓࡀാ࠸࡚⣽⬊࿘ᮇࢆ G1 ᮇ௨እࡢࢫࢸ࣮ࢪ࡛೵Ṇࡉࡏ࡚࠸ࡿࡇ࡜ࡀ⪃࠼ࡽࢀࡿࠋࡑࡋ࡚ษ่᩿⃭࡟ࡼࡾࠊS ᮇᚋ༙࡛⣽⬊࿘ᮇࢆ೵Ṇࡉࡏࡿไᚚᶵᵓࡀゎ㝖ࡉࢀࠊ(A) S ᮇᚋ༙࠿ࡽࡢ⣽⬊࿘ᮇ෌㛤ࠊ(B) DNA ቑᖜࢆక࠺⣽⬊࿘ᮇ෌㛤ࠊ (C) DNAಟ᚟⣔ࢆ⏝࠸ࡓ⣽⬊࿘ᮇ෌㛤ࡢ࠸ࡎࢀ࠿ࡀ㉳ࡇࡿࡢ࡛ࡣ࡞࠸࠿࡜⪃࠼ࡽࢀࡿࠋ
ࡲࡓ⣽⬊ࡢᛶ㉁ኚ໬ࢆᘬࡁ㉳ࡇࡍࡓࡵ࡟ࡣࠊࡑࡢ⣽⬊ࡀಖᣢࡋ࡚࠸ࡿ≉␗ⓗ࡞㑇ఏᏊⓎ⌧ࣃࢱ࣮ࣥࢆษࡾ᭰࠼ࡿᚲせࡀ࠶ࡾࠊS ᮇ࡛ࡑࢀࡀ࠾ࡇࡿྍ⬟ᛶࡣඛ࡟㏙࡭ࡓࠋࡲࡓ G2 ᮇ࡛ࡶࠊࡑࡢࡼ࠺࡞ኚ໬ࢆ㉳ࡇࡍ᫬ᮇ࡛࠶ࡿࡇ࡜ࡀ࣐࢘ࢫࡢጞཎ⏕Ṫ⣽⬊࡛ศ࠿ࡗ࡚ࡁࡓࠋጞཎ⏕Ṫ⣽⬊࡟࠾
ࡅࡿ G2 ᮇ࡛ࡢ೵ṆࡣࠊDNA ࡢ࣓ࢳࣝ໬ࣃࢱ࣮ࣥࡢኚ໬௨እ࡟ࡶࠊࣄࢫࢺࣥಟ㣭ࡢኚ໬ࡀ࠾ࡇࡿ
(Seki et al., 2007; Hyldig et al., 2011)ࠋࡲࡓጞཎ⏕Ṫ⣽⬊ࡀ G2 ᮇ࡛೵Ṇ࡛ࡁ࡞࠸ࣀࢵࢡ࢔࢘ࢺ࣐࢘
ࢫ࡛ࡣࠊࡑࡢࡼ࠺࡞ࣄࢫࢺࣥಟ㣭ࡀ㉳ࡇࡽ࡞࠸ (Pirouz et al., 2013)ࠋࡇࢀࡽࡢࡇ࡜ࢆ⪃៖ࡍࡿ࡜ࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢ S ᮇᚋ༙࡛೵Ṇࡋ࡚࠸ࡿⴥ⣽⬊ࡣࠊษ᩿ᚋ࡟」〇ࡉࢀ࡚࠸࡞࠸㡿ᇦࡢ DNA」〇࡟ຍ࠼ࠊG2 ᮇ࡟ධࡿ࡜ࣄࢫࢺࣥಟ㣭ࡢࡼ࠺࡞࢚ࣆࢪ࢙ࢿࢸ࢕ࢵࢡಟ㣭ࡢኚ໬ࢆཷࡅࠊ⣽⬊ᛶ㉁ኚ໬ࢆㄏᑟࡋ࡚࠸ࡿྍ⬟ࡶ⪃࠼ࡿࡇ࡜ࡀ࡛ࡁࡿࠋ

㸲. ⣽⬊࿘ᮇไᚚᅉᏊ࡟ࡼࡿ⣽⬊࿘ᮇ࡜⣽⬊ᛶ㉁ኚ໬ࢆ⤫ᚚࡍࡿศᏊᶵᵓḟ࡟ᖿ⣽⬊໬࡟࠾ࡅࡿ⣽⬊࿘ᮇ࡜⣽⬊ᛶ㉁ኚ໬ࡢ⤖ࡧ௜ࡁࢆㄪ࡭ࡿࡓࡵࠊ࠸ࡃࡘ࠿ࡢ⣽⬊࿘ᮇࡢ㐍⾜ࢆ㜼ᐖࡍࡿ⸆๣ࢆຍ࠼࡚ࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊໬ࡢᵝᏊࢆㄪ࡭࡚ࡳࡓࠋ࢔ࣇ࢕ࢹ࢕ࢥ࡛ࣜࣥษ᩿ⴥࢆฎ⌮ࡍࡿ࡜ࠊษ᩿ᚋࡢ DNA ྜᡂ࡜⣽⬊㉁ศ⿣ࡀᢚไࡉࢀࡓࡀࠊཎ⣒య⣽⬊ࡢ≉ᚩࡢࡦ࡜ࡘ࡛࠶ࡿඛ➃ᡂ㛗ࡸཎ⣒య≉␗ⓗ㑇ఏᏊࡢⓎ⌧ࡀほᐹࡉࢀࡓ (ᅗ 4; Ishikawa et al.,2011)ࠋ୍᪉ࠊCDK άᛶࢆ㜼ᐖࡍࡿࣟࢫࢥࣅࢳ࡛ࣥฎ⌮ࡍࡿ࡜ࠊDNA ྜᡂ࡜⣽⬊㉁ศ⿣ࡔࡅ࡛࡞
M. Ishikawa- 5BSJ- Revi ew 6: 45 ( 2015)

植物科学最前線 6: 46 ( 2015)ᅗ㸲. ษ᩿ᚋࡢⴥ⣽⬊ࡢኚ໬ࢆ⾲ࡋࡓᶍᘧᅗ
㸯.㔝⏕ᆺࠊ↓ฎ⌮ࡢሙྜࠊษ᩿㠃࡟᥋ࡋࡓ⣽⬊ࡀᖿ⣽⬊໬ࡋࠊ⣽⬊ศ⿣࡜ඛ➃ᡂ㛗ࡀ࠾ࡇࡿࠋ㸨ࡣࢡࣟࣟࢿ࣐㡬➃ᖿ⣽⬊ࢆ♧ࡍࠋ
2.ษ᩿ⴥࢆ࢔ࣇ࢕ࢹ࢕ࢥ࡛ࣜࣥฎ⌮ࡋࡓሙྜࠋ⣽⬊ศ⿣ࡣᢚไࡉࢀࡿࡀࠊඛ➃ᡂ㛗ࡣ࠾ࡇࡿࠋ
3.ษ᩿ⴥࢆࣟࢫࢥࣅࢳࣥࠊࢻ࣑ࢼࣥࢺࢿ࢞ࢸ࢕ࣈ CDKA ࢆ㐣๫Ⓨ⌧ࡉࡏࡓሙྜࠋ⣽⬊ศ⿣࡜ඛ➃ᡂ㛗ࡢ୧᪉ࡀᢚไࡉࢀࡿࠋ
4. wox13la wox13lb ஧㔜㑇ఏᏊḞኻᰴࡢษ᩿ⴥࠋඛ➃ᡂ㛗ࡣᢚไࡉࢀࡿࡀࠊ⣽⬊ศ⿣ࡣᢚไࡉࢀ࡞࠸ࠋ㙨ࡣ⣽⬊㉁ศ⿣ࢆ♧ࡋ࡚࠸ࡿࠋࡃࠊඛ➃ᡂ㛗࡜ཎ⣒య≉␗ⓗ㑇ఏᏊⓎ⌧ࡶᢚไࡉࢀࡓ (ᅗ 4; Ishikawa et al., 2011)ࠋ࡝ࡕࡽࡶ⣽⬊࿘ᮇࡢ㐍⾜ࢆᢚไࡍࡿ⸆๣࡛࠶ࡿࡀࠊ࢔ࣇ࢕ࢹ࢕ࢥࣜࣥࡣ DNA ࣏࣓࣮ࣜࣛࢮάᛶࢆ㜼ᐖࡍࡿࡇ࡜࡛ DNA 」〇ࢆᢚไࡋࠊ⣽⬊࿘ᮇࡢ㐍⾜ࢆṆࡵࡿࠋ୍᪉ࣟࢫࢥࣅࢳࣥࡣࠊCDK ࡢ࢟ࢼ࣮ࢮάᛶ
M. Ishikawa- 6BSJ- Revi ew 6: 46 ( 2015)

植物科学最前線 6: 47 ( 2015)ࢆᢚไࡍࡿࡇ࡜࡛ࠊ⣽⬊࿘ᮇࡢ㐍⾜ࢆṆࡵࡿࠋࡇࢀࡽࡢࡇ࡜࠿ࡽ 2 ࡘࡢ㜼ᐖ๣࡟ࡼࡿ⾲⌧ᆺࡢ㐪࠸ࡣࠊCDK ࢟ࢼ࣮ࢮάᛶࡢ㐪࠸࡟ࡼࡿྍ⬟ᛶࡀ⪃࠼ࡽࢀࡓࠋࡑࡇ࡛ࠊ࢟ࢼ࣮ࢮ୙άᛶᆺࡢ CDKA;1ࢆࣄ࣓ࢶࣜ࢞ࢿࢦࢣ࡛㐣๫Ⓨ⌧ࡉࡏࡿࡇ࡜࡛ࠊෆᅾᛶࡢ CDKA ࡢ࢟ࢼ࣮ࢮάᛶࢆᢚไࡉࡏࡿ࡜ࠊ
ࣟࢫࢥࣅࢳࣥฎ⌮࡜ྠᵝ࡟ษ᩿ᚋࡢ⣽⬊ศ⿣࡜㡬➃ᡂ㛗ࡀᢚไࡉࢀࡓ (ᅗ 4; Ishikawa et al., 2011)ࠋ
ࡇࢀࡽࡢࡇ࡜࠿ࡽࠊCDKAࡀ⣽⬊࿘ᮇࡢ㐍⾜࡜⣽⬊ఙ㛗ࡢ୧᪉ࢆไᚚࡋ࡚࠸ࡿࡇ࡜ࡀศ࠿ࡗࡓ㸦ᅗ5㸧ࠋゝ࠸᥮࠼ࢀࡤࠊᖿ⣽⬊໬ࡢ㐣⛬࡛ࡣࠊ⣽⬊࿘ᮇࡢ㐍⾜࡜⊂❧ࡋ࡚⣽⬊ࡢᛶ㉁ኚ໬ࢆㄏᑟࡍࡿ
ศᏊᶵᵓࡀാ࠸࡚࠾ࡾࠊCDKA ࡀࡑࡢศᏊᶵᵓࢆไᚚࡋ࡚࠸ࡿ࡜ゝ࠺ࡇ࡜ࡀ࡛ࡁࡿࠋ
ࡇࡢ⣽⬊ࡢᛶ㉁ኚ໬ࢆㄏᑟࡍࡿศᏊᶵᵓࡣࠊ࣓࣍࢜࣎ࢵࢡࢫ㑇ఏᏊࡢ୍ࡘ࡛࠶ࡿ
WUSCHEL-RELATED HOMEOBOX 13-LIKE (WOX13L) ࡢゎᯒ࠿ࡽࠊࡑࡢ୍➃ࡀぢ࠼ጞࡵ࡚ࡁࡓࠋ
WOX13L 㑇ఏᏊࡣࠊࢩࣟ࢖ࢾࢼࢬࢼࡢ WOX13 㑇ఏᏊࡢ࢜ࣝࢯࣟࢢ࡛࠶ࡾࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣ࡟ࡣࠊWOX13LAࠊWOX13LBࠊWOX13LC ࡢ୕ࡘࡢ㑇ఏᏊࡀᏑᅾࡋ࡚࠸ࡿ (Deveaux et al., 2008;Sakakibara et al., 2014)ࠋWOX13LA ࡜ WOX13LB ࡢ஧ࡘࡢ㑇ఏᏊࢆ◚ቯࡋࡓኚ␗య࡛ࡣࠊ⣽⬊㉁ศ
⿣ࡣ㉳ࡇࡿࡀࠊࢡࣟࣟࢿ࣐㡬➃ᖿ⣽⬊ࡢ≉ᚩ࡛࠶ࡿ㡬➃ᡂ㛗ࡣᢚไࡉࢀࡿ (ᅗ 4; Sakakibara et al.,2014)ࠋࡘࡲࡾࠊWOX13L 㑇ఏᏊࡣࠊ⣽⬊࿘ᮇไᚚ࡜ࡣ⊂❧ࡋࡓᖿ⣽⬊໬࡟࠾ࡅࡿඛ➃ᡂ㛗ࡢࣉࣟࢢ࣒ࣛࢆไᚚࡋ࡚࠸ࡿ࡜࠸࠺ࡇ࡜ࡀ᫂ࡽ࠿࡟࡞ࡗࡓ㸦ᅗ 5㸧ࠋᅗ㸳. ⣽⬊࿘ᮇࡢ෌㛤࡜⣽⬊ᛶ㉁ࡢኚ໬ࢆ⤫ᚚࡍࡿ௙⤌ࡳ⌧᫬Ⅼ࡛ࠊ࡝ࡢࡼ࠺࡟ࡋ࡚CDKAࡀ⣽⬊ࡢᛶ㉁ኚ໬ࠊࡘࡲࡾඛ➃ᡂ㛗ࢆไᚚࡋ࡚࠸ࡿࡢ࠿ࡣ୙
࡛᫂࠶ࡿࡀࠊࡇࢀࡲ࡛ࡢື≀ࡸࢩࣟ࢖ࢾࢼࢬࢼࡢ▱ぢࢆྜࢃࡏ࡚ࠊ୍ࡘࡢྍ⬟ᛶࢆ⪃࠼࡚ࡳࡓ࠸ࠋ
ࢩࣟ࢖ࢾࢼࢬࢼࡢⴥ࠿ࡽࡢ࢝ࣝࢫᙧᡂ࡟ࡣࠊࢤࣀ࣒࣡࢖ࢻࡢࣄࢫࢺࣥ H3K27me3 ࡢኚ໬ࡀᚲせ࡛࠶ࡿ (He et al., 2012)ࠋࡲࡓື≀ࡢᇵ㣴⣽⬊࡛ࡣࠊCDKA ࡢ࣍ࣔࣟࢢ࡛࠶ࡿ Cdk1 ࡀࠊ࣏ࣜࢥ࣮࣒ᢚไ」ྜయ (PRC2) ࢆᵓᡂࡍࡿᅉᏊ Ezh2 ࢆࣜࣥ㓟໬ࡍࡿࡇ࡜࡛ࠊEzh2 ࡢࣄࢫࢺ࣓ࣥࢳࣝ໬
άᛶࢆไᚚࡋࠊࣄࢫࢺࣥ H3K27me3 ࡢ㢖ᗘࢆኚ໬ࡉࡏࡿ (Chen et al., 2010)ࠋࣄ࣓ࢶࣜ࢞ࢿࢦࢣ
࡟ࡶ PRC2 ࢆᵓᡂࡋ࡚࠸ࡿᅉᏊࡣᏑᅾࡋ࡚࠾ࡾ (Mosquna et al., 2009; Okano et al., 2009)ࠊࡑࡢ࠺
ࡕࡢ୍ࡘ FIE 㑇ఏᏊࡣࠊᖿ⣽⬊໬ࡢ㐣⛬࡛Ⓨ⌧ࡀୖ᪼ࡍࡿࡢ࡛ࠊᖿ⣽⬊໬࡟㛵ࢃࡗ࡚࠸ࡿࡢ࡛ࡣ࡞࠸࠿࡜⪃࠼ࡽࢀ࡚࠸ࡿ (Mosquna et al., 2009)ࠋࡑࡇ࡛ࠊษ᩿ᚋ࡟άᛶ໬ࡉࢀࡓ CDKA ࡣࠊศ⿣ࢆ೵Ṇࡋ࡚࠸ࡿⴥ⣽⬊ࡢ⣽⬊࿘ᮇࢆ෌㛤ࡉࡏࡿ࡜࡜ࡶ࡟ࠊPRC2 ࡢᵓᡂᅉᏊࢆࣜࣥ㓟໬ࡍࡿࡇ࡜࡛ࠊࡑࡢ㓝⣲άᛶࡸࢤࣀ࣒DNA࡜⤖ྜ⬟࡞࡝ࢆኚ࠼ࡿࡇ࡜࡛ࠊࢤࣀ࣒࣡࢖ࢻ࡟ࣄࢫࢺࣥ H3K27
ࡢ࣓ࢳࣝ໬≧ែࢆኚ࠼ࠊ
⣽⬊࿘ᮇ௨እࡢ⣽⬊ᛶ㉁ኚ໬ࢆㄏᑟࡋ࡚࠸ࡿࡢ࡛ࡣ࡞࠸࠿࡜⪃࠼࡚࠸ࡿࠋ
M. Ishikawa- 7BSJ- Revi ew 6: 47 ( 2015)

植物科学最前線 6: 48 ( 2015)ࡇࡢ௬ㄝࢆ᳨ドࡍࡿࡓࡵ࡟ࡣࠊCDKA ࡢᶆⓗᅉᏊࢆྠᐃࡍࡿ࡜࡜ࡶ࡟ࠊCDKA ࡢ࢟ࢼ࣮ࢮάᛶ
࡟ࡼࡗ࡚ࣄࢫࢺࣥಟ㣭≧ែࡀ࡝ࡢࡼ࠺࡟ኚ໬ࡍࡿࡢ࠿ㄪ࡭ࡿࡇ࡜ࡀᚲせ࡛࠶ࢁ࠺ࠋ㸳. ௒ᚋࡢᒎᮃ㝣ୖ᳜≀㛫࡛ࡢࢤࣀ࣒ẚ㍑࠿ࡽࠊ⣽⬊࿘ᮇไᚚᅉᏊࡔࡅ࡛࡞ࡃᇶᮏⓗ࡞㑇ఏᏊࢭࢵࢺࡣ㝣ୖ᳜≀㛫࡛ಖᏑࡉࢀ࡚࠸ࡿ (Banks et al., 2011)ࠋࡲࡓࠊࢩࣟ࢖ࢾࢼࢬࢼࡢ CDKA ࡀ⣽⬊࿘ᮇไᚚࡔࡅ
࡛࡞ࡃࠊᖿ⣽⬊ࡢᛶ㉁ࢆไᚚࡋ࡚࠸ࡿࡇ࡜ࡀ♧ࡉࢀ࡚࠸ࡿࡢ࡛ (Gaamouche et al., 2010)ࠊࣄ࣓ࢶ
ࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊໬࡟࠾ࡅࡿ༠ㄪⓗไᚚᶵᵓࡀࠊ㝣ୖ᳜≀඲య࡛ࡶᶵ⬟ࡋ࡚࠸ࡿྍ⬟ᛶࡣ኱ࡁ࠸࡜ண᝿ࡉࢀࡿࠋࡑࡢࡓࡵࠊࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊໬㐣⛬࡟࠾ࡅࡿ CDKA ࡢᶵ⬟ࡢゎ᫂ࡣࠊ⿕Ꮚ᳜≀ࡢⓎ⏕࠾ࡼࡧ෌⏕㐣⛬࡟ぢࡽࢀࡿᖿ⣽⬊໬ࡢ⣽⬊ᛶ㉁ࡢኚ໬࣭⥔ᣢ࡟ᑐࡋ࡚⤫୍ⓗ࡞⌮ゎ࡟㈉⊩࡛ࡁࡿࡇ࡜ࡀᮇᚅࡉࢀࡿࠋࡉࡽ࡟ࡣࠊ࡝ࡢࡼ࠺࡟ࡋ࡚⣽⬊࿘ᮇไᚚᅉᏊ࡛࠶ࡿ CDKA ࡀࠊ⣽⬊࿘ᮇ௨እࡢ⣽⬊ᛶ㉁ࡢኚ໬ࢆㄏᑟࡉࡏࡿࡢ࠿ࠊࡑࡢศᏊᇶ┙ࢆ᫂ࡽ࠿࡟ࡍࡿࡇ࡜࡛ࠊື᳜≀ࢆၥࢃࡎࠊከ⣽⬊⏕≀ࡢศ໬≧ែ࡜ᖿ⣽⬊≧ែࡢ 2 ࡘࡢ≧ែࡀኚືࡍࡿ࡜ࡁࡢศᏊᶵᵓࢆゎࡁ᫂࠿ࡍ㘽ࡀᚓࡽࢀࡿࡢ࡛ࡣ࡞࠸࠿࡜ᮇᚅࡉࢀࡿࠋ

㸴. ㅰ㎡ᮏ✏࡛⤂௓ࡋࡓࣄ࣓ࢶࣜ࢞ࢿࢦࢣࡢᖿ⣽⬊໬◊✲ࡣࠊ୺࡟ ERATO 㛗㇂㒊ศ໬඲⬟ᛶ㐍໬ࣉࣟࢪ࢙ࢡࢺ࡛⾜ࢃࢀࡓࠋࡲࡓᮏ◊✲ࢆ㐍ࡵࡿ࡟࠶ࡓࡾࠊᩘࠎࡢࡈຓゝࡸᐇ㦂ࡢࢧ࣏࣮ࢺࢆ㡬࠸ࡓࠊᇶ♏⏕≀Ꮫ◊✲ᡤࡢ㛗㇂㒊ගὈ ᩍᤵࠊᮧ⏣㝯 ༤ኈࠊ᪥Ώ♸஧ ༤ኈࠊERATO 㛗㇂㒊ࣉࣟࢪ࢙ࢡࢺ࡛࠾ୡヰ࡟࡞ࡗࡓ಴⏣ဴஓ ༤ኈࠊஂಖ⛱ ༤ኈࠊబ⸨Ⰻ຾ ༤ኈࠊすᒣᬛ᫂ ༤ኈࠊᴬཎᜨᏊ ༤ኈ࡟ࠊࡇࡢሙࢆ೉ࡾ࡚࠾♩⏦ࡋୖࡆࡲࡍࠋ㸵. ᘬ⏝ᩥ⊩Banks, J.A., Nishiyama, T., Hasebe, M., Bowman, J.L., Gribskov, M., et al. 2011. The Selaginella genome
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